Been reading some wiki articles about various sleep disorders and hallucinations, and there is one called the "Tetris effect" . I think most players have experienced this with minesweeper where when you're falling asleep, you can see a minesweeper board and/or are playing minesweeper. Also minesweeper dreams are pretty common.

Another 2009 Oxford study suggests that playing Tetris-like video games may help prevent the development of traumatic memories. If the video game treatment is played soon after the traumatic event, the preoccupation with Tetris shapes is enough to prevent the mental recitation of traumatic images, thereby decreasing the accuracy, intensity, and frequency of traumatic reminders.